Process for shifting the dyestuff equilibrium of 1:2 metal complex azo-dyes



United States Patent 3,239,302 PROCESS FOR SHlFTiNG THE DYESTUFF EQUI- LlBRlUh l 0F 1:2 METAL COMPLEX AZO-DYlES Utto Albrecht, deceased, late of Munchenstein, Switzerland, by Vally Albrecht, administratrix, Munchenstein, Switzerland, assignor to Ciba Limited, Basel, dwitzerland, a company of Switzerland No Drawing. Filed Get. 3, 1960, Ser. No. 60,210 Claims priority, application Switzerland, Nov. 28, 1955, 27,148/55 4 Claims. (Cl. 8-43) This application is a continuation-in-part of my application Serial No. 611,357, filed September 21, 1956 (now US. Patent No. 2,963,513).

The so-called 1:2 metal complex dyes are complex metal compounds of azo dyes, preferably o,o-dihydroxy monoazo compounds which are as a rule free from sulfonic acid or carboxylic groups. In place of these groups they contain sulfamide, alkane sulfone or similar groups enhancing water-solubility. The complex is formed by two molecules of the azo-dye reacting with one chromium atom or cobalt atom. The 1:2 metal complex dyes exhibit fundamentally different dyeing behaviour as compared with the dyestuffs containing sulfonic acid groups. In the case of the latter dyes, level results are achieved by the process of boiling on and off, i.e., boiling is prolonged until a dynamic equilibrium between the dye on the fiber and the dye in the liquor has been established. This process of migration takes place only to a very small extent in the case of 1:2 metal-complex dyes. Thus, the 1:2 metal-complex dyes show quite a different dyeing behaviour as compared with the level dyeing acid dyes or the 1:1 metal complex dyes.

Surprisingly it has now been found that level dyeing of basic nitrogen containing fibers with 1:2 metal complex dyes is established when dyeing is effected in the presence of a polyethylene glycolether of certain primary monoamines,

The present invention concerns a process for shifting the equilibrium of the distribution of a 1:2 metal complex azo-dye between an aqueous liquor and basic nitrogenous fibers to establish a level dyeing, in which metal complex one metal atom selected from the group consisting of chromium and cobalt is bound in complex union with two molecules of an azo-dyestuif and which metal complex contains at most one strongly acid solubilizing group, which process comprises effecting the dyeing in aqueous medium and in the presence of 0.5 to 4 percent, calculated on the weight of the fibrous material, of a levelling agent obtained from additively combining 50 to 100 mols of ethylene oxide with one mol of a mixture of unsubstituted saturated straight-chained aliphatic primary monoamines containing an even number of at least 16 and at most 22 carbon atoms; at least 30 percent by weight of the mixture contain amines having an even number of at least 20 and at most 22 carbon atoms.

As basic nitrogenous fibers are considered fibers containing substantial amounts of linear combined units having the grouping NH-. The nitrogen containing textile fibers having a basic character may be selected from natural fibers, such as wool and silk, and from synthetically produced polyamide fibers containing -CONH groups, such as condensation products from saturated dicarboxylic acids and alpha,omega-diamines, by condensation of w-aminocarboxylic acids or by polymerization of e-caprolactam. In the process of the invention there are preferably dyed wool fibers and synthetically produced polyamide fibers.

The term strongly acid solubilizing group means a group which exhibits significant acidic behaviour in aqueous solution such as the COOH and SO H group. The dyes used in the process of the invention contain besides sulfonamide groups, -SO N or alkane sulfonyl groups, SO -alkyl, no strongly acid solubilizing group or at most one. The 1:2 metal complex may contain two similar or dissimilar azo dyestuffs. Exam ples of dyes of the defined type are shown in the examples.

The levelling agents which are used in the process of the invention are polyethyleneglycol ethers of a mixture of unsubstituted unbranched saturated primary aliphatic monoamines, which polyethyleneglycol ethers correspond to the general formula in which n is an even number of at least 14 and at most 20, x and z are integers and the sum of x-l-z is at least 50 and at most 100, preferably about 70, with the proviso that n is at least 18 and at most 20 in at least about 30% by weight of said primary amines, preferably in 3090 percent.

Amines suitable as starting materials are mixtures consisting of palmitic amine, stearic amine, arachidyl amine and behenylamine; 30 to 90 percent of the mixtures contain arachidyl amine and/or behenylamine.

The reaction of these amine mixtures with ethylene oxide produces additively combined {CH CH OEI- groups, i.e., the hydrogen atoms attached at the nitrogen atoms are substituted through subsequently combined groups. The reaction is carried out advantageously at a raised temperature and with the exclusion of atmospheric oxygen, advantageously in the presence of a suitable catalyst, for example, a small amount of an alkali metal or an alkali metal hydroxide, carbonate or acetate.

The amount of additively combined ethylene oxide is critical. Suitable polyglycol ether derivatives for the process hereinbefore referred to are obtained by reacting a quantity of ethylene oxide such that the reaction product contains an average of 50-100 CH -CH O groups. Particularly good results are obtained by using products containing between and 75 groups, i.e., about CH CH -O groups.

The polyglycol ethers can be converted in known manner into salts, for examples, acetates, or if desired into quaternary ammonium salts, and used in this form.

With the defined 1:2 metal complex dyestuffs wool or other nitrogenous fibers can be dyed in known manner usually from weakly acid, for example, acetic acid, to neutral baths. Preferably dyeing is effected at a range of pH between 3.0 and 7.5, advantageously between 3.5 and 7.0. In order to produce a levelling effect, or in order to avoid the tippy dyeing of the nitrogenous fibers, the polyglycol ethers may be added to the dyebath at the same time as the dyestuff. However, it is especially advantageous first to treat the fibrous material, for example, wool, advantageously at a raised temperature, in a bath containing the polyglycol ether, and to add the dyestuff later. Usually dyeing is completed after boiling for about 30-90 minutes. The dye bath may contain other ingredients such as acetic acid, formic acid, sulfuric acid, ammonium sulfate and sodium sulfate. The quantity of the polyglycol ether derivative to be added to the dyebath may vary within wide limits. Usually, for example, a quantity within the range of 0.5 to 4 percent calculated on the weight of the fibrous material, may be added, It is especially advantageous to add to the dyebath a quantity of the polyglycol ether within the range of 0.5 to 1.5 percent calculated on the weight of the,

fibrous material, the quantity of the polyglycol ether being, for example, about 50 percent calculated on the weight of the dyestuff added. In dyeing by the process of this invention not only can the aforesaid levelling effect be produced, which, inter alia, can be utilized for the level dyeing of wools having different properties, for example, chlorinated and unchlorinated wool, but further advantageous efiects can be observed, for example that the fastness to rubbing of the dyeings is not impaired thereby, whereas it is considerably reduced when other levelling agents previously proposed are used.

The following examples illustrate the invention, the parts and percentages being by weight:

Example 1 Three samples of 13.7 parts (corresponding to 1 molecular proportion) of an ordinary commercial mixture of primary alkylamines containing about percent of palmitylaniine, percent of stearylamine, 20 percent of archidylamine and 10 percent of behenylamine are heated to fusion in a current of nitrogen, then to each sample 0.14 part of sodium is added and the whole is heated to 160 C. Ethylene oxide is then introduced in a finely distributed gas stream at 160-170" C. until in the first sample 111 parts (corresponding to molecular proportions), in the second sample 154 parts (corresponding to 70 molecular proportions) and in the third sample 220 parts (corresponding to 100 molecular proportions) of ethylene oxide have been absorbed. At a reaction temperature of 160-170 C. it takes about 3 hours before the reaction sets in. The total reaction period is about 10-14 hours. It is of advantage in the above reactions to produce the fine distribution of ethylene oxide with the aid of a glass frit. The products so obtained are wax-like masses which are easily soluble in water. Hereinafter they are designated levelling agent A (containing 50 mols of additively combined ethylene oxide), levelling agent B (70 mols) and levelling agent C (100 mols).

Example 2 12 parts (corresponding to 1 molecular proportion) of an ordinary commercial mixture of primary alkylamines, containing about 10 percent of stearylamine, percent of arachidylamine and 35 percent of behenylamine, are heated in a current of nitrogen at 170 C., then 0.12 part of metallic sodium is added, and ethylene oxide is introduced at 160170 C. in the form of a finely distributed gas stream until 121 parts (corresponding to molecular proportions) thereof have been absorbed. The absorption of ethylene oxide is very slow at first and becomes brisker only after a reaction period of about 5 hours. When obtained in this manner, the reaction product is a wax-like mass which is easily soluble in water. It is designated levelling agent D.

Example 3 15 parts (corresponding to 1 molecular proportion) of the mixture of primary alkylamines used in Example 2 are heated to 170 C. in a current of nitrogen, 0.15 part of metallic sodium is added, and ethylene oxide is introduced at 160170 C. in the form of a finely distributed gas stream until 108.5 parts (corresponding to 50 molecular proportions) thereof have been absorbed. The reaction product is a wax-like mass which is easily soluble in water. It is designated levelling agent E. The correspondingly prepared product with molecular proportions of ethylene oxide is designated levelling agent F.

Example 4 15 parts (corresponding to 1 molecular proportion) of arachidylamine or 16 parts (corresponding to 1 molecular proportion) of behenylamine are reacted with parts of ethylene oxide (corresponding to about 70 molecular proportions) in the manner described in Example 1.

There is obtained a water-soluble product which can be used as a levelling agent for 2:1 metal complex dyes.

Example 5 100 parts of wool piece goods are entered at 50 C. into a bath which contains in 4000 parts of water 4 parts of acetic acid of 40 percent strength, 20 parts of sodium sulfate containing water of crystallization and 0.5 part of the levelling agent B of Example 1. 1 part of the complex chromium compound of the dyestuff of the formula which compound contains 2 molecules of monoazo-dyestufi bound in complex union with one atom of chromium, is dissolved in a small amount of water, and the solution is added to the dyebath. The temperature is raised in the course of 30-45 minutes to the boil and dyeing is carried on for /2 hour at the boil. The wool piece goods are then rinsed in the cold and dried. There is obtained a level blue dyeing of good fastness to rubbing.

By dyeing unchlorinated and chlorinated wool in the same manner in one bath, each of these two kinds of wool is dyed practically the same tint, whereas without the addition of the polyglycol ether derivative the chlorinated wool is much more strongly dyed.

Instead of the aforesaid dyestutl there may be used for dyeing in the above manner the metal compounds of the dyestuffs of the formulae II O OH I I C C H:

N=NC CHN- g (cobalt compound) I S 02 HNC H3 O H 11C) (chromium com ound I p O C S O 2 I HN-CHa which also contain two molecules of monoazo-dyestutf bound in complex union to one atom of metal, or a mixture of these dyestuffs may be used.

Example 6 100 parts of wool piece goods are entered at 50 C. into a bath which contains 4 parts of ammonium sulfate in 4000 parts of water, 1 part of the bordeaux-dyeing cobalt complex of the dyestutf of the formula which contains two molecules of monoazo-dyestutf bound in complex union to one atom of cobalt, is added dissolved in a small amount of water, and the whole is gradually heated to the boil in the course of 45 minutes and then boiled for a further /2 hour.

The steam is turned off, and then 4 parts of acetic acid of 40 percent strength and 0.5 part of the levelling agent B as described in Example 1 are added to the liquor. Boiling is then continued for a further 30-60 minutes until the full shade has been developed. The dyeing is then finished in the usual manner. There is obtained a substantially more level dyeing than is obtained without the addition of the levelling agent.

In the same manner more level dyeings can be produced with the yellowish red-dyeing chromium complex of the dyestuff of the formula HO-C N s t N 2 Example 7 In the following dyeing processes (a), (b) and (c) the dyestuffs were added to the bath after boiling the bath for minutes. In each sample 100 parts of the fibers were dyed in 4000 parts of water containing 4 parts of acetic acid of 40 percent strength and parts of sodium sulfate containing water of crystallization. In addition, the baths contained the following fibers, levelling agents and dyestuffs:

(a) A woven article of a synthetically produced polyamide fiber of the nylon type, 1 part of levelling agent A and 0.5 part of the brown dyestuff of the formula OH OH -N=N NH0 0 CH ((chromium compound) I No; CH3

(b) A woven article of a synthetically produced polyamide fiber of the w-aminocarboxylic acid type, 4 parts of levelling agent C or D and 0.5 part of one of the dyestuffs of Formulas l and 2 (cobalt compound) S02 CH3 violet-brown (c) A woven article of a synthetically produced polyamide fiber of the e-caprolactarn type, 1.5 parts of (chromium compound) OH ([)H OzN (J black (chromium compound) H O blue What is claimed is:

1. A process for shifting the equilibrium of the distribution of a 1:2 metal complex azo-dye between an aqueous liquor and basic nitrogenous fibers to establish a level dyeing, in which metal complex one metal atom selected from the group consisting of chromium and cobalt is bound in complex union with two molecules of an azo-dyestuff and which metal complex contains at most one strongly acid solubilizing group, which process comprises efiecting the dyeing in aqueous medium and in the presence of 0.5 to 4 percent, calculated on the weight of the fibrous material, of a levelling agent obtained from additively combining 50 to 100 mols of ethylene oxide with one mol of a mixture of unsubstituted saturated straight-chained aliphatic primary monoamines containing an even number of at least 16 and at most 22 carbon atoms; 30 to per cent by weight of the mixture contain amines having an even number of at least 20 and at most 22 carbon atoms.

2. A process for shifting the equilibrium of the distribution of a 1:2 metal complex azo-dye between an aqueous liquor and Wool fibers to establish a level dyeing, in which metal complex one metal atom selected from the group consisting of chromium and cobalt is bound in complex union with two molecules of an azo-dyestufi? and which metal complex contains at most one strongly acid solubilizing group, which process comprises effecting the dyeing in aqueous medium and in the presence of 0.5 to 4 percent, calculated on the weight of the fibrous material, of a levelling agent obtained from additively combining 50 to 100 mols of ethylene oxide with one mol of a mixture of unsubstituted saturated straight-chained aliphatic primary monoamines containing an even number of at least 16- and at most 22 carbon atoms; at least 30 percent by weight of the mixture contain amines having an even number of at least 20 and at most 22 carbon atoms.

3. A process for shifting the equilibrium of the distribution of a 1:2 metal complex azo-dye between an aqueous liquor and synthetically produced polyamide fibers to establish a level dyeing, in which complex one metal atom selected from the group consisting of chromium and cobalt is bound in complex union with two molecules of an azo-dyestulf and which metal complex contains at most one strongly acid solubilizing group, which process comprises effecting the dyeing in aqueous medium and in the presence of 0.5 to 4 percent, calculated on the weight of the fibrous material, of a levelling 20 4. A process for shifting the equilibrium of the distribution of a 1:2 metal complex azo-dye between an aqueous liquor and basic nitrogenous fibers to establish a level dyeing, in which metal complex one metal atom selected from the group consisting of chromium and cobalt is bound in complex union with two molecules of an azo-dyestutf and which metal complex contains at most one strongly acid solubilizing group, which process comprises effecting the dyeing in aqueous medium and in the presence of 0.5 to 4 percent, calculated on the weight of the fibrous material, of a levelling agent obtained from additively combining about 70 mols of ethylene oxide with one mol of a mixture of unsubstituted saturated straight-chained aliphatic primary monoamines containing an even number of at least 16 and at most 22 carbon atoms; at least 30 percent by weight of the mixture contain amines having an even number of at least 20 and at most 22 carbon atoms.

References Cited in the file of this patent UNITED STATES PATENTS 2,763,530 Schuetz et al. Sept. 18, 1956 2,903,325 Geigy Sept. 8, 1959 25 2,963,513 Albrecht Dec. 6, 1960 

1. A PROCESS FOR SHIFTING THE EQUILIBRIUM OF THE DISTRIBUTION OF A 1:2 METAL COMPLEX AZO-DYE BETWEEN AN AQUEOUS LIQUOR AND BASIC NITROGENOUS FIBERS TO ESTABLISH A LEVEL DYEING, IN WHICH METAL COMPLEX ONE METAL ATOM SELECTED FROM THE GROUP CONSISTING OF CHROMIUM AND COBALT IS BOUND IN COMPLEX UNION WITH TWO MOLECULES OF AN AZO-DYESTUFF AND WHICH METAL COMPLEX CONTAINS AT MOST ONE STRONGLY ACID SOLUBILIZING GROUP, WHICH PRICESS COMPRISES EFFECTING THE DYEING IN AQUEOUS MEDIUM AND IN THE PRESENCE OF 0.5 TO 4 PERCENT, CALCULATED ON THE WEIGHT OF THE FIBROUS MATERIAL, OF A LEVELLING AGENT OBTAINED FROM ADDITIVELY COMINING 50 TO 100 MOLS OF ETHYLENE OXIDE WITH ONE MOL OF A MIXTURE OF UNSUBSTITUTED SATURATED STRAIGHT-CHAINED ALIPHATIC PRIMARY MONOAMINE CONTAINING AN EVEN NUMBER OF ATR LEAST 16 AND AT MOST 22 CARBON ATOMS; 30 TO 90 PER CENT BY WEIGHT OF THE MIXTURE CONTAIN AMINES HAVING AN EVEN NUMBER OF AT LEAST 20 AND AT MOST 22 CARBON ATOMS. 